new & recent described Flora & Fauna species from all over the World esp. Asia, Oriental, Indomalayan & Malesiana region

Wednesday, May 17, 2017

[Entomology • 2017] Melitaea acentria • A New Species of Melitaea from Israel, with Notes on Taxonomy, Cytogenetics, Phylogeography and Interspecific Hybridization in the Melitaea persea complex (Lepidoptera, Nymphalidae)

Specimens with intermediate morphology are often considered to be the result of ongoing interspecific hybridization; however, this conclusion is difficult to prove without analysis of chromosomal and/or molecular markers. In the butterfly genus Melitaea, such an intermediacy can be detected in male genitalia, and is more or less regularly observed in localities where two closely related, presumably parental species are found in sympatry. Here I analyze a high altitude Melitaea population from Mt. Hermon in north Israel and show that its male genitalia are clearly differentiated from those found in phenotypically similar M. persea and M. didyma, but in some aspects intermediate between them. This hybrid-like population is unique because, although M. didyma is present on Mt. Hermon, the true, low-altitude M. persea has never been reported from Israel. Cytogenetic analysis revealed no apomorphic chromosomal characters to distinguish the Mt. Hermon population from other known taxa of the M. persea and M. didyma species groups. At the same time, DNA barcode-based phylogeographic study showed that this population is ancient. It was estimated to originate 1–1.6 million years ago in the Levantine refugium from a common ancestor with M. persea. Generally, the data obtained are incompatible with interpretation of the studied population as a taxon conspecific with M. persea or M. didyma, or a swarm of recent hybrids between M. persea and M. didyma, although the possibility of ancient homoploid hybrid speciation cannot be ruled out. I also argue that the name Melitaeamontium assigned to butterflies from north Lebanon cannot be applied to the studied taxon from Mt. Hermon. Here I describe this morphologically and ecologically distinct entity as a new species Melitaeaacentria sp. n., and compare it with other taxa of the M.persea complex.

Distribution: Melitaeaacentria is known to occur at high altitudes (1730–2060 m above the sea level) of Mt. Hermon (Fig. 11). Within these altitudes it is sympatric and syntopic with M. trivia syriaca, M. deserticola and M. cinxia. At the altitudes 1730–1780 m there is an essential overlapping of the M. acentria and M. didyma liliputana ranges where both species were found to fly together in early May 2016. Two other Melitaea species known from Mt. Hermon, M. collina and M. telona, were found to fly mostly at lower altitudes 1000–1600 m.

Etymology: The name acentria is a noun of the feminine gender. This name originates from the Greek prefix “a” that means “not” and from the Latin word “centrum” (centre) derived from the Greek “κέντρον” (kentron, a sharp point). Acentria is the Internet nickname of Asya Novikova who collected the samples initiated this research.This name indicates also the peripheral position of the new species within the distribution range of the M. persea species complex.

The identity and taxonomic status of the M. persea-similar samples from north Lebanon, Jordan, Iraq, Pakistan, and Afghanistan remain still unclear. The populations from Lebanon characterized by the mitochondrial haplogroup P2 (Fig. 9) could actually represent (i) a distinct subspecies of M. persea, (ii) an undescribed subspecies of M. acentria, or even (iii) an undescribed species. Further morphological, molecular and chromosomal studies are required to select between these hypotheses.

Vladimir A. Lukhtanov. 2017. A New Species of Melitaea from Israel, with Notes on Taxonomy, Cytogenetics, Phylogeography and Interspecific Hybridization in the Melitaeapersea complex (Lepidoptera, Nymphalidae). Comparative Cytogenetics. 11(2); 325-357. DOI: 10.3897/CompCytogen.v11i2.12370